Electric fusible cut-out.



H. P. LIVERSIDGB.

. ELECTRIC PUSIBLE GUT-OUT4 APPLICATION, FILED APR. 9. 1E) 13.

Patented Jan. 5, 1915.

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O. 8 2, K NN A1 2 l 1 UNITED STATES PATENT urinoir..

HORACE PRESTON LIVERSIDGE, l0F BALA, PENNSYLVANIA, ASSI'NUR. T0 PENNSYL-VANIA APPLIANCE COMPANY, OF PHILADL'FH'A, PENNSYIFANIA, A GQRPQR- TION0F NEW JERSEY.

ELECTRIC FUSIBLE CUT-C-UT.

Specification of Letters Patent.

Patented .Er-in. 5, MM5.

To all whom it may concern:

Be it known that I, HORACE PRESTON Llvnnsmeu, of Bala, in the county ofMontgomery and State of Pennsylvania, have invented certain new anduseful Improvements in Electric Fusible Cut-Outs, whereof the followingis a specification, reference being had to the accompanying drawings.

My invention relates to a fusible cut-out for electric circuits of theexpulsion type, in which the fusing of the cut-out by which the circuitis broken, releases a compressed gas or liquid, which is thereuponexpelled with suflicient force to blow out the electric arc otherwiseformed upon the breaking of the electric circuit.

It has heretofore been proposed to construct so-called expulsion fusesin which the heat of an arc if formed releases compressed gas and blowsout the arc; but in such cases,A

the release of the compressed gas has been effected by the employment toconfine the gas, of a fusible plug, not in the electric circuit itself,but merely in proximity to the fusible section of the electric circuit,so that the formation of an are by the meltingof a portion of suchcircuit, may communicate suicient heat to melt the fusible plug whichrestrains the compressed gas; but in such constructions the release ofgas is uncertain, since the heat of the are may not melt the fusibleplug.

It is characteristic of my invention that I make the fusible portion ofthe electric circuit itself the means of restraining the compressedfluid, so that the melting and consequent breaking of the circuit ofnecessity effects the release of the fluid.

In the accompanying drawings, Figure 1, is a plan view of a fusiblecut-out embodying my invention. Fig. Il, is a vertical longitudinalsection of the same. Fig. III, is an end elevation with the receptaclefor holding the container for the compressed gas opened.

In the accompanying drawings, the holder or casing 1, is provided with apivoted end piece 2, which carries the links 3, pivot 4, and handle 5.It may be secured in closed position by placing the pivot 4, beneath thelug 6. Other means for closing the holder may be employed. To the openend of the holder is attached an insulating sleeve 10, the other end ofwhich is provided with a suitable contact terminal 11. .A second contactterminal 12, is attached to or forms a part of the holder l, su that thetwo Contact ter minals are separated by the insulating sleeve 10.

The interior of the holder 1, is shaped to contain the nie-taillereceptacle lili, containing compressed Huid. To the open end of thisreccptable attached a metallic tube 16, the end of the tube beingexpanded with in the contracted opening cf the receptacle to form aiermctically closed joint. The metallic tube '1.6, of electricallyconductive metal and (in part at least) fusilif-ie. it is provided witha restricted arca if?, bevond which it is closed at 1S, by menus ot unictul clamp 19, which is connected by the wire Q0, to the binding clampQ1. electrically connected to the contact terminal 11. Similarly themetal contact pipe 30, which is electrically connected to the contactterminal 12, is clamped around the tube lli., near the end which isattached to the receptacle l5. The fusible tube 1G, is surrounded by alarger tube 33, of electrically non-conduct- .ing refractory material,such as asbestos, which forms a protector' and facilitates thc blowingout of thc` fuse,

The fusible tube 1.6, forms a 'part of the electric circuit whichconnects the contacts 1l, and l2, as has been above explained. Thenarrowed portion of the tube is the point which will first melt in casethe tube becomes overheatcd from carrying a heavier electrical currentthan that for which it intended. ln case of the melting of the tube 1G,the compressed tiuid prcferabljif car bon-dicxd, contained within thereceptacle 15, and the tube 1G. necessarily finds an outlet at the pointof fusion The iud thus escaping forms a. blast oi considerable forcewhich instantly bleus the ,hmm and of the tube 16. out of the end of tli inl i $33. This effectually prevents the 4 nist... arc, since thevoiatiic gases upon which formation of an are is dependent, are iustantiy dissipated bj; the explosire force of the escaping fluid. Furthermore.thc @seaping Huid by reason ci' Lits expansion cools down the pointwhere the circuit is broken preventing volatiliration. vit will be notedthatl certain and efiicient action of the eX pelled fluid is compelledby the fact that a part of the container of the fluid` that is the tube16, itself forms a part of the electrical circuit, so that the meltingof the fnsibc portion of this circuit, to 'break 'the circuit, of itselfreleases the fluid, without the necesi sity of the further communicationofheat resulting from the formation of an are to a second fusible iece,by which compressed gas is restraine as has heretofore been suggested 1nprevious expulsion fuses.

`I Iaving thus tescribed my invention, I c im:

1. A fusible cut-out for safe arding electric circuits comprising ametnic receptacle for a compressed iiuid, .a ortion of said receptaclebeing fusible, sani) receptacle and its fusible portion both forming apart of the circuit to be safeguarded.

2. A metallic receptacle, containing fluid under ressure rovided with anaperture closed y a pro onged structure of-fusible metal, saidreceptacle and the prolonged structure which closes it formingsuccessive parts of a continuous permanent electrical parts,

conductor, the overheating of which by excessive current melts thefusible metal structure and simultaneously releases fluid presrsure fromthe metallic receptacle.

3. A fusible cut-out for electric circuits comprising a metallicreceptacle for a com- Fremd lfluid; a fusible extension thereon, hemelting of which opens the receptacle, an electric circuit of which saidreceptacle and its fusible extension form continuous and a larger tubesurrounding ysaid tubular extension open at the end away from thereceptacle.

In testimony whereof, I have hereunto signed any name at Philadelphia,Pennsyl- Vania., this fth `dev of April, 1913.

HORACE PRESTON LIVERSlDGll`- Witresses: H B

Mss ma., E. L. Fmnn'rou.

